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41.
The neutral component of d-mannan of bakers' yeast (Saccharomyces cerevisiae), consisting solely of d-mannose residues, was precipitated with concanavalin A to give four fractions. The first three displayed similar reactivities in quantitative precipitin reaction against concanavalin A and homologous anti-S. cerevisiae serum, but the fourth showed different precipitin curves. Analysis of the fractions by acetolysis indicated structural differences. The different behavior of the last fraction in precipitin reactions could be due to a lower content of branching points, or to shorter chain-lengths. 相似文献
42.
The rubella seroimmunity status of a total of 1,204 students aged 12 to 19 in a junior and a senior high school in Osaka district was surveyed. Among these, 487 students (40.5%) were found to be seronegative (less than 1 : 8) by the hemagglutination inhibition (HI) test. A total of 287 students were immunized with live rubella vaccine, Biken lot No.7233. This caused an increased titer in all except one of the 262 seronegative students, while among 25 students with an initial HI antibody titer of 1 : 8 it caused more than 4-fold increase in 20 and 2-fold increase in 5. The vaccine caused no clinical manifestations, such as fever, rash or arthralgia. 相似文献
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44.
H. Ueda Takeshi Baba Nobuo Terada Yasuko Kato Shigeo Tsukahara Shinichi Ohno 《Histochemistry and cell biology》1997,108(3):243-248
It is known that the retina contains the protein dystrophin in the ribbon synapse, but the ultrastructural analysis is not
yet fully elucidated. Our previous study reported that dystrophin is localized under the rod cell membranes in rat retinas.
In the present study, we have investigated the relationship between dystrophin-rich regions of rod cell membranes and other
neuronal processes in mouse retinas with a monoclonal antibody raised against the human dystrophin C-terminus. Immunoblotting,
immunofluorescence stainings, and immunoelectron microscopy were employed. Immunoblotting analysis indicated that mouse retinas
possessed some of the dystrophin isoforms of approximately 260 kDa, 140 kDa, and 70 kDa molecular weight. Confocal images
showed a punctate appearance in the outer plexiform layer, as previously described. Immunoelectron microscopy showed that
dystrophin immunoreactive products were always observed at submembranous dense regions of the rod spherule abutting bipolar
processes. These results suggest that retinal dystrophin may be closely involved in signal transmission from rods to bipolar
cells.
Accepted: 7 May 1997 相似文献
45.
Shizuya Tanaka Toshiro Kato Shigeo Yamamoto Hirosuke Yoshioka 《Bioscience, biotechnology, and biochemistry》2013,77(10):1953-1959
Since S-n-butyl S′-p-tert-butylbenzyl N-3-pyridyldithiocarbonimidate, a potent fungicide to powdery mildew, is known to inhibit ergosterol biosynthesis in Monilinia fructigena, the activities were assessed on 24 compounds having other substituents than the 3-pyridyl and on 24 compounds having a variety of different structures connecting the 3-pyridyl and the p-tert-butylphenyl group from that of the dithiocarbonimidate.In the former group the 3-pyridyl group was essential for the activities and the substitution at the 2- or 6-position resulted, on available data, in inactive compounds. Several other β-N-heterocyclic analogs were also active. In the latter group, a number of modified compounds from the dithiocarbonimidate structure were shown to be active. 相似文献
46.
Masuko Suzuki Takeshi Mikami Tatsuji Matsumoto Shigeo Suzuki 《Microbiology and immunology》1977,21(8):419-425
The Limulus test has been considered specific for the presence of bacterial endotoxins. To synthesize a simple model of endotoxin, palmitoyldextran phosphate was prepared by modification of dextran by palmitoylation and phosphorylation. The present studies indicated that a variety of polysaccharide derivatives, such as palmitoyldextran phosphate, palmitoyldextran, and dextran phosphate, give a positive Limulus test and show pyrogenic activity, except for low molecular dextran derivatives. On the other hand, polysaccharides, such as dextran, starch (soluble), chitosan, xylan, and lentinan, were negative in these assays. The gelation reaction of Limulus lysate by modified dextran derivatives may depend on the molecular weight or modification of polysaccharides by palmitoylation and/or phosphorylation to a great extent. 相似文献
47.
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49.
Yoshihiro Nishino Shigekazu Takemura Yukiko Minamiyama Kazuhiro Hirohashi Tetsuya Ogino Masayasu Inoue 《Free radical research》2013,47(4):373-379
Vancomycin hydrochloride (VCM), a glycopeptide antibiotic, has a broad spectrum against methicillin-resistant Staphylococcus aureus (MRSA). As it is known to induce renal dysfunction, the dose and the duration of its administration are limited. Moreover, the mechanism of VCM-induced renal dysfunction remains to be unclear. To evaluate the involvement of free radical on VCM-induced renal dysfunction, we carried out analysis with a hexamethylenediamine-conjugated superoxide dismutase (AH-SOD) which rapidly accumulates in renal proximal tubule cells and inhibits oxidative injury of the kidney. Male Wistar rats (weighing 200-210 g) were intraperitonealy administered with 200 mg/kg of VCM twice a day for 7 days. AH-SOD 5 mg/kg/day was subcutaneously injected 5 min before every VCM injection. VCM induced renal injury dose-dependently. Biochemical analyses revealed that plasma levels of blood urea nitrogen and creatinine significantly increased in the VCM-treated group by an AH-SOD-inhibitable mechanism. VCM simultaneously elicited an increase of 8-OHdG levels and chemiluminescence intensity of free radical generation in the kidney. Histological examination revealed that VCM also elicited a marked destruction of glomeruli and necrosis of proximal tubules. AH-SOD inhibited these phenomena in the kidney. These results suggested that oxidative stress might underlie the pathogenesis of VCM-induced nephrotoxicity and targeting SOD and/or related antioxidants to renal proximal tubules might permit the administration of higher doses of VCM sufficient for eradication of MRSA without causing renal injury. 相似文献
50.
Tomoyuki Yamanaka Asako Tosaki Masaru Kurosawa Kazunori Akimoto Tomonori Hirose Shigeo Ohno Nobutaka Hattori Nobuyuki Nukina 《PloS one》2013,8(12)
Cell polarity plays a critical role in neuronal differentiation during development of the central nervous system (CNS). Recent studies have established the significance of atypical protein kinase C (aPKC) and its interacting partners, which include PAR-3, PAR-6 and Lgl, in regulating cell polarization during neuronal differentiation. However, their roles in neuronal maintenance after CNS development remain unclear. Here we performed conditional deletion of aPKCλ, a major aPKC isoform in the brain, in differentiated neurons of mice by camk2a-cre or synapsinI-cre mediated gene targeting. We found significant reduction of aPKCλ and total aPKCs in the adult mouse brains. The aPKCλ deletion also reduced PAR-6β, possibly by its destabilization, whereas expression of other related proteins such as PAR-3 and Lgl-1 was unaffected. Biochemical analyses suggested that a significant fraction of aPKCλ formed a protein complex with PAR-6β and Lgl-1 in the brain lysates, which was disrupted by the aPKCλ deletion. Notably, the aPKCλ deletion mice did not show apparent cell loss/degeneration in the brain. In addition, neuronal orientation/distribution seemed to be unaffected. Thus, despite the polarity complex disruption, neuronal deletion of aPKCλ does not induce obvious cell loss or disorientation in mouse brains after cell differentiation. 相似文献